How to Choose the Right Box & Calculate Shipping Costs

How to Choose the Right Box & Calculate Shipping Costs

When it comes to packaging, buying the perfect sized box really does matter and so does properly working out your shipping costs ahead of time. These are simple fundamentals that help you to reduce waste and to keep your costs down, giving you more money in your budget to spend somewhere else!

Getting these elements right has a big impact on both small and large businesses. And, if you stock a range of products that vary in size, it will be worth running through this guided process for each one.

So let’s get started.

Choosing the perfect sized box

The general rule of thumb is to buy a box that is as close to your product size as possible and there are 3 good reasons why you should stick to this.

  1. It will eliminate or reduce the number of fillers required

  2. Create a better unboxing experience for your customers

  3. It will cost you less in packaging and shipping

Win-win all around for you, your customers and the environment!

So how do you work out the right sized box?

Simply start by measuring the length, width and height of your product.

Then determine if your product is fragile and breakable. 

For products such as coffee or clothing, protective fillers will not be required. But, if you’re shipping glass, crockery, or electrical items you will need to allow space in your box for protective fillers.

We recommend creating a 2inch or 5-6cm layer between the product and box when using protective packaging fillers.

So once you have the measurements of your product and accounted for fillers (if required), it’s time to look for the perfect sized box.

At Boxed-Up we have created a Box Finder Tool, which allows you to simply enter your desired measurements and we will provide you with the best matching boxes for your product!

It’s important to note that it is general practice for box suppliers to list the internal dimensions of a box, which you need to keep in mind when choosing the perfect sized box. 

Working Out Shipping Costs

Once you have your product in its box with any necessary fillers, it is then time to work out your shipping costs!

Start by measuring the external size and the weight of your box.

Shipping companies will be factoring in how your box will fit on shipping pallets in transit as well as weight, so will need both sets of information to provide you with a quote.

It is then worth comparing different shipping providers, factoring in cost, time scale and if you’re shipping within the UK or internationally.

Or if you intend to use the Royal Mail postal service, we have some postal size brackets and costs here for you.

We also have more detailed Royal Mail packaging guides for Large Letter, Small and Medium sized parcels where you can find some great extra tips on safely packaging your products.

You should now be ready to work out the perfect sized box for your items and key pointers for figuring out your shipping costs. 


If you have any questions, please get in touch with our expert team.